Seismic tools are often used to capture information about seismic activity by positioning the seismic tool in a subterranean borehole or well. For accurate seismic measurement, the seismic tools are mechanically coupled to the formation/reservoir downhole by establishing firm contact with a borehole wall or other structure exposed seismic activity in the formation.
Seismic tools are often tractored into horizontal wells, with gravity being employed for coupling the sensor to the wellbore. These tractors are powered by conductors in a cable, with the available power being limited by conductors and cable length. The use of heavier seismic tools, for enhanced gravitational coupling, is problematic with respect to energy and space limitations in the downhole environment.
Some seismic tools use motors to engage locking arms that coupled to the formation, but the use of such systems can be frustrated by complications associated with power supply and machine control.